Extraction behaviors of platinum group metals in simulated high-level liquid waste by a hydrophobic ionic liquid bearing an amino moiety

摘要

A hydrophobic ionic liquid including an amino moiety ([DiOcAPmim][NTf2]) was synthesized. Its extraction behaviors towards Pd(II), Ru(III), Rh(III) were investigated in nitric acid aqueous solution as a function of contact time, effect of concentration of nitric acid, effect of temperature, and effect of co-existing metal ions. The extraction kinetics of Pd(II) was fairly fast and extraction equilibrium can be attained within only 5?min under the [HNO3]?=?2.05?M. When [HNO3]< 1?M, the extraction percentage of Pd(II), Ru(III), Rh(III) were all above 80%. When [HNO3] reached 2?M, all of the extraction percentage decreased and in an order of Pd(II)>Ru(III)>Rh(III). When [HNO3]> 2?M, the extraction performance gradually recovered. The effect of temperature can slightly affect the extraction performance of Pd(II). Furthermore, in simulated high-level liquid waste, [DiOcAPmim][NTf2] showed a better preference towards Pd(II) under the interference of various other co-existing metal ions.